Brake booster rod / clevis problem

[pbcanney]

ran into a bit of a conundrum today.

In reinstalling the brake booster into my 81 , which was an automatic when I took it out, and now has pedals from a 79....

The clevis was about an inch and a half away from the pedal where the pin slides into the brake pedal.

I reinstalled it, as is, but the brake pedal was about 2 inches closer to the floor (than the clutch pedal). Not knowing if this is "normal" I continued hooking up the wiring under the dash, and when I install the the brake light switch, that is activated when pressing on the brake, I cant get it to make a contact with the switch (even all the way pushed into the bracket)

So I removed it, thinking unscrewing the rod in hopes it was adjustable, but it just spins

So here are my questions...

Should the rod be adjustable?

Is there a different booster for manual transmissions?

Is there a different push rod that the cleavis mounts on for manuals.

anyone have a booster with rod and cleavis of known good quality out that can measure from the flat of the booster where the 4 bolts mount to the hole of the cleavis.?

this really knocked the wind out of my sails today. especially having to pull the booster out after fighting with those 4 mounting bolts for an hour installing it.

;help

 

[SPANISHVETTS]

I ran into a problem like this when building the SBC rock climber.

I made an extension for the rod by threading the servo rod out of the booster* and connecting it to a piece of threaded bar stock with a long barrel nut.

It has been working for over 5 years of serious off road trashing so I guess that it is safe.

*use a quality die and plenty of cutting oil. The servo rod on my booster was really hard to thread.

 

[pbcanney]

The more I think about this, I am beginning to think that the p/o may have swapped in a booster from a different gm product somewhere along the way. It doesn't make sense that everything I put into the 81, came from a 79 C3, and unless my research is way off, the pedal assembly was the same as well as the booster.

So, if I could just get a measurement from the backside of the booster (where it goes through the firewall) to the hole in the cleavis (the U shaped piece that 'pins' to the brake pedal), of a known good one, that would confirm or reject my conclusions.

I dont mind buying a booster, if it needs one. But I dont want to buy one, just because.

 

[pbcanney]

c'mon gang... I'm desperate here.


I posted a similar Q at CF and got some responses, but now I need to know about pedals.

If you have a 4 speed stock C3 , can you describe the clutch and brake pedals in relation to each other? One other has told me that his brake pedal is apprx 2 inches lower than the clutch. (same issue I am having)

Is that normal for everyone?

another raised the point that maybe the clutch pedal should be lowered.

but that wouldnt solve the brake light switch not reaching the paddle on the brake.

Is there an extension on the brake booster rod I am missing?

;help

 

[Crimson Thunder]

My 70(without power brakes)has the clutch pedal about 2 inches higher than the brake pedal.When i got the car the clutch return spring was unattached and the pedals were closer together.When i reattached the spring it raised the clutch pedal back up and accually makes the car harder to drive.

 

[pbcanney]

Apparently, there is a "bumper" that attaches to the inside of the pedal cage that keeps the clutch pedal from coming "way" up. I can't find a picture of how big it is, but I ordered one from Corvette Central for a couple of bucks. Mine doesnt have one, stopping on the metal of the cage itself. But that doesnt answer my pin/switch dilemna

Thank you for responding

My 70(without power brakes)has the clutch pedal about 2 inches higher than the brake pedal.When i got the car the clutch return spring was unattached and the pedals were closer together.When i reattached the spring it raised the clutch pedal back up and accually makes the car harder to drive.